1. Field of the Invention
The present invention relates to a system and method for machining process characterization.
2. Background Art
The ever-increasing emphasis on product quality continues to put pressure on manufacturers to find new ways to produce high quality products without increasing production time or otherwise increasing manufacturing costs. Inherent in this high quality, low cost dichotomy is a need to reduce scrap, while obtaining the longest possible life from manufacturing tools and equipment. Thus, increasing the number of tooling changes and/or decreasing the time between machine tool maintenance may increase product quality, but it may result in an unnecessary increase in tooling costs and/or lost production time.
Over time, manufacturers have developed systems and methods of predictive and preventative maintenance. Such systems may include a scheduled tool change based on a number of parts produced, or scheduled machine down time, during which bearings and other components may be replaced prior to their having an adverse effect on product quality. In order to implement these systems in a cost effective manner, decision-makers need information. In particular, information that is indicative of historical trends is useful, so that accurate predictions can be made regarding future production runs. In addition, the ability to isolate particular problem areas is also useful; this helps to concentrate efforts where they will have the most impact and produce the most benefit.
Toward this end, manufacturers have continued to analyze machine tools and their associated components in an effort to gather information they can use to make efficacious decisions regarding their production systems and processes. One type of machine tool analysis used is a vibration analysis. Information gathered from this type of analysis may be indicative of a variety of different production problems.
One system and method of characterizing a machining process using vibrational signatures of machines is described in U.S. Pat. No. 5,663,894, issued to Seth et al. on Sep. 2, 1997. Seth et al. describes characterizing the vibrational signatures of machines by discriminating vibrational activity at various positions on the machines. This is done both with and without machining loads. Both time and frequency domain analysis may then be stored in a database for future comparison and tracking.
Although other systems and methods exist for analyzing various machine operation parameters, such as vibrations, none provides a mechanism for isolating the data and managing it to develop an operation-specific data matrix. Such information may be useful to a manufacturing decision-maker, particularly in a multi-tool, Computer Numerical Control (CNC) machine environment.
Accordingly, there exists a need for a system and method of machining data management for a machine tool having multiple cutting tools, such that data profiles of individual operations are easily analyzed, and such that the data profiles may be processed to provide an operation-specific data matrix and operation-specific trend lines.